1. Field of Invention
The invention is directed to fracturing tools for use in oil and gas wells, and in particular, to fracturing tools capable of directing fracturing fluid in a direction that is parallel to the casing before the fracturing fluid enters the perforations in the wellbore.
2. Description of Art
Fracturing or “frac” systems or tools are used in oil and gas wells for completing and increasing the production rate from the well. In deviated well bores, particularly those having longer lengths, fracturing fluids can be expected to be introduced into the linear, or horizontal, end portion of the well to frac the production zone to open up production fissures and pores therethrough. For example, hydraulic fracturing is a method of using pump rate and hydraulic pressure created by fracturing fluids to fracture or crack a subterranean formation.
In addition to cracking the formation, high permeability proppant, as compared to the permeability of the formation can be pumped into the fracture to prop open the cracks caused by a first hydraulic fracturing step. For purposes of this disclosure, the proppant is included in the definition of “fracturing fluids” and as part of well fracturing operations. When the applied pump rates and pressures are reduced or removed from the formation, the crack or fracture cannot close or heal completely because the high permeability proppant keeps the crack open. The propped crack or fracture provides a high permeability path connecting the producing wellbore to a larger formation area to enhance the production of hydrocarbons.
During fracturing operations, the fracturing fluid is directed from the fracturing tool at a high rate of flow and into a blast liner that redirects the fracturing fluid out of the fracturing tool and into the inner wall surface of the casing within in the well. The fracturing fluid then flows downward in the annulus of the well, i.e., between the outside of the fracturing tool or tool string to which the fracturing tool is connected and the inner wall surface of the wellbore or casing disposed in the wellbore, until it reaches the perforations in the wellbore that are to be packed with the fracturing fluid. As a result of the fracturing fluid flowing out of the fracturing tool and into the inner wall surface of the casing, the casing can be damaged, e.g., eroded by the fracturing fluid impacting the inner wall surface of the casing as soon as it leaves the fracturing tool.